Hydraulic check device for looms



July 10, 1956 A. E. ZARN 2,753,895

HYDRAULIC CHECK DEVICE FOR LOOMS Filed April 9, 1954 INVENTOR.

BY S:

United States Patent r ce HYDRAULIC CHECK DEVICE FOR LOOMS Adolphe EmileZarn, Zurich, Switzerland, assignor to Pneumafil Corporation, Charlotte,N. C., a corporation of Delaware Application April 9, 1954, Serial No.422,175

6 Claims. (Cl. 139-161) This invention relates to a hydraulic checkdevice for looms and more particularly to a hydraulic check deviceadapted to cushion movement of the picker stick during operation of theloom.

Hydraulic check devices heretofore used have their braking effectadjusted automatically in accordance with the requirements of the loom.This improves the efficiency of the loom and the quality of the fabricsWoven on the loom. A disadvantage, however, is an increase in the lengthof the lay so that it is impossible to fit the check device in somemills because of lack of space. The results obtained by checking theshuttle of the loom led to experimental work to cushion the picker stickafter striking. The space available underneath the lay of the looms isgenerally too small to permit the conventional hydraulic check device tobe placed therein. Where, however, it is possible to place theconventional hydraulic check device underneath the lay of the looms, asaving of material and a marked decrease in loom vibrations is obtained.

The chief object of the present invention is to provide a new hydrauliccheck device for weaving looms adapted to cushion movement of the pickerstick in either direction and which can be fitted easily underneath thelay of the loom.

An object of the invention is to provide an inexpensive hydraulic checkdevice for weaving looms which comprises a housing filled with oil andcompressed air and containing tapered recesses for movement of pistonsplaced within the housing. One piston operates when the shuttle ishitting a picker and the other when the picker stick strikes. Thecushioning effect is obtained in both utmost positions of the pickerstick. Other objects of the invention will be readily perceived from thefollowing description.

This invention relates to a hydraulic check device for looms adapted tocushion movement of the picker stick in either direction which comprisesin combination a housing adapted to be placed beneath the lay of theloom, the housing including two tapered recesses and being partiallyfilled with oil and the balance with compressed air, pistonsreciprocable in said recesses, mechanism connected to said pistons, saidmechanism being adapted to be engaged by the picker stick upon movementthereof whereby the pistons serve to cushion movement of the pickerstick of the loom, one of said pistons serving to brake movement of theincoming shuttle of the loom, the second piston serving to cushionmovement of the picker stick when striking.

The attached drawing illustrates a preferred embodiment of the inventionin which Figure 1 is a sectional View through the hydraulic checkdevice;

Figure 2 is a sectional View through the check device shown in Figure 1;and

Figure 3 is a diagrammatic view illustrating the fitting of the checkdevice underneath the lay of the loom.

2,753,895 Patented July 10, 1956 Referring to the attached drawing thereis shown the check device of the present invention which includes an airand oil type housing 1 fitted underneath the lay 3 of the loom by meansof a plate 2 emerging from the housing 1; the housing contains twotapered recesses 4 and 5. Pistons 6 and 7 are placed in the recesses 4and 5 of the housing and are movable back and forth therein. Pistons 6and 7 slide in bearings 8 and 9. Rubber rings 10 and 11 are provided toseal against loss of oil. To prevent dust from entering the housing,rubber rings 12 and 13 are provided in the bearings. Both pistons 6 and7 are provided with cross pins 14 and 15 which limit the forward strokeof the piston by contacting or hitting stop rings 16 and 17.

A recess 18 in housing 1 serves as an air tank. An inlet valve 20 isplaced in the housing about at the oil level 19 and is removed when theoil is poured in the housing. Inlet valve 20 is placed at the oil levelin order to prevent oil from flooding the air chamber or recess 18.Recess 18 may be filled with compressed air by means of a hand pump (notshown) connected through the inlet valve.

Piston 6 is connected by its head 21 to a sling 22 surrounding thepicker stick 23 (refer to Figure 3).

In operation of the check device as shown in Figure 3 the incomingshuttle is hitting or striking the picker 24 and is brought to rest. Toprotect the wooden picker stick 23, a cover plate or cap 25 is providedon sling 22. From the moment the shuttle contacts picker 24, the pickerstick 23 is slowed down until it comes to rest in its utmost backposition (shown in dotted lines in Figure 3) because of the brakingeffect of piston 6 when pushed into the oil filled recess 4. The shuttleis maintained in this utmost position by a binder or brake tongue (notshown).

Piston 7 is pushed in the cylinder 5 when the picker stick 23 hits head26 with full speed. Although the speed of the picker stick is now verymuch higher than during the former braking operation in the left endposition the adjustable braking effect of the outflowing oil insuressmooth braking. The conventional spring (not shown) at the picker stickfoot will pull the stick back until it again comes to a rest on sling22. The utmost positions of the picket stick are shown in dotted lines.

It will be understood the embodiment of the invention illustrated in thedrawing can be altered if desired. For example, it is not necessary tolocate the two pistons or plungers one above the other, since pistonscould be placed in other suitable locations. It is not necessary thatboth pistons work in the same oil since if desired, a wall couldseparate the pistons thereby providing two separate oil compartments.The check device checks or brakes the picker stick in either directionand its special location underneath the lay of the loom avoids anincrease in the length of the lay.

While I have described a preferred embodiment of the invention, it willbe understood the invention is not limited thereto since it may beotherwise embodied within the scope of the following claims.

I claim:

1. In a loom having a lay, a shuttle, and a picker stick: a hydrauliccheck device serving to cushion movement of the picker stick in eitherdirection, said check device comprising the combination of a housingadapted to be placed beneath the lay of the loom, said housing includingtwo tapered recesses and being filled partially with oil and the balancewith compressed air, pistons reciprocable in said recesses, mechanismconnected to said pistons, said mechanism being adapted to be engaged bythe picker stick upon movement thereof whereby said pistons serve tocushion movement of the picker stick of the loom, one of said pistonsserving to brake movement of the incoming shuttle of the loom, thesecond piston serving to cushion movement of the picker stick whenstriking.

2. A hydraulic check device according to claim 1 in which a slingconnects the picker stick to the first piston.

3. A hydraulic check device according to claim 2 in which a cap isprovided on the end of the sling to contact the picker stick.

4. A hydraulic check device according to claim 1 in which the recessesare connected by a duct.

5. A hydraulic check device according to claim 1 in which the pistonsare placed one above the other.

6. A hydraulic check device according to claim 1 including an inletvalve placed at the level of the oil contained in the housing.

References Cited in the file of this patent UNITED STATES PATENTSCornins July 2, 1901 Balogh May 9, 1950 Hufierd Feb. 6, 1951 FOREIGNPATENTS Great Britain June 4, 1952

